bertola



J. A: BERTOLA.

7' Ore Amalgamator No. 18,485. v

ater fled Oct 20,1857.

UNITED STATES PATENT OFFICE.

JOSEPH A. BERTOLA, OF NEW YORK, N. Y., ASSIGNOR TO HIMSELF AND JOHNSTAGG, OF SAME PLACE.

AMALGAMATOR.

Specification of Letters Patent No. 18,485, dated October 20, 1857.

To all whom it may concern Be it known that I, JOSEPH ALOIDE BER- TOLA,late of Turin, but now of New York, county of New York, and State of NewYork, have invented certain new and useful Improvements in Machinery forAmalgamating the Precious Metals with Mercury; and I do hereby declarethat the following is a full, clear, and exact description of the same,reference being made to the annexed drawing, making a part of thisspecification, in which Figure I is perspective view of my amalgamator.Fig. II is a transverse vertical section thereof.

Similar letters indicate similar parts throughout.

My machine for amalgamating gold and silver ore with mercury consists ofa tub secured upon a strong frame in such manner as to be capable ofbeing tilted over, 2'. 6. may rock upon an axis. The sides of this tubmay be of wood or metal, but the bottom should for greater durability bealways of metal. This is put in in the form of a false bottom, so thatwhen worn out it can be easily and cheaply replaced without disturbingthe other parts of the machine. In this tub there is a revolving muller,which is driven around by a shaft, but so as to allow its weight to restupon the bottom, and in such manner also as will permit it to be readilydisengaged at the tines when the tub is to be tilted to empty itscontents. Two openings for emptying are employed. The first is to beused to draw off the water and refuse, and the other to empty theamalgamated mercury. The first spout is therefore a little above thebottom, while the latter is about upon a level with it. At A isacircular tub, which I prefer to have made with the sides flaring. Thisis set upon a base B, supported in a strong frame by a journal or boltplaced at about the middle, as at (c). It is, while in operation, to bekept in a longitudinal position, and for this purpose a wedge shapedblock (d) fits in a space made for the purpose upon the front crossrail, a button ((Z) keeping it in. When the wedge (d) is in place theback of the bed rests upon the back cross rail (6) Fig. II. The falsebottom is seen at Fig. II; it has an upright post or pin cast upon it atits center, and which pin, entering a cavity in the muller, keeps thelatter in a central position in the tub as it revolves. At (k) is thespout for drawing off the ground ores after they have been suflicientlyacted upon and while the tub is maintained in its level position; thespout, it will be seen, has its interior orifice a little above thefalse bottom, as has already been mentioned. At (k) is seen the spoutfor pouring off the amalgamated mercury, and, as is shown, has itsorifice very nearly or quite on a level with the bottom. Into a tub thusconstructed is placed a revolving muller, and this is not to beconsidered either as an agitator simply, or as a grinding apparatus, butits office is to effect the bringing of all the particles of solidmatter, however finely divided or pulverized previous to beingintroduced into the tub, into intimate contact with the quicksilver. Acertain degree of pressure upon the bottom is one of the conditionsnecessary, and another is the mode in which the materials are agitatedto insure the passing of all regularly under the bottom of the saidmuller. For effecting this it is constructed to act as a partitiondividing the tub into two compartments from top bottom, or nearly so, orat least to the height at which the ground ores are admitted. If themuller were of metal of these dimensions (in a full sized mill) it wouldbe too heavy. I make it therefore of a block of wood, and face itsbottom with iron or other metal. The muller is seen at L, shaped as across-bar with its sides concave, and its ends tapering to the shape ofthe side of the tub. The concavity is for the purpose of insuringequality of wear of the bottom, as by this means the surface is enlargedoutward toward the ends and since the rate of wear increases in theproportion of the space passed over. The muller L is made to rotate by aspindle (0) which enters at its lower end into a cross arm fitting upontwo pins upon the top of the muller so as to allow of play and also thatthe arm may be readily removed, which is done by slipping it upon thesquare part of the spindle, when the muller is set free. This isrequired to be done before tilting the tub. The bottom of the muller isalso grooved like a mill stone. From the above it will be seeen that theores containing the precious metals, and which are to be amalgamatedwith the mercury, are to be treated by a somewhat lengthened operation,and in this it differs from other amalgamators wherein the mixtures areflowing in and out of the amalgamating vessels in a constant stream;consequently the mercury can act in those only upon such particles asare brought in contact with it, and which contact is effected in variousways but always in a transient manner. Hence the great waste, but by myprocess a given quantity of materials are only acted upon at a time andwhich action is maintained for the required period to effect theamalgamation of the greatest quantity possible out of such givenmaterials, and the results of which plan have proved successful. Theoperation is therefore as follows: A slow and regular revolution of themuller L to be maintained by a suitable power. The spouts (7s) and areto be plugged up. The pulverized ores containing the precious metals areintroduced in a mixture of water until the tub is nearly full; themercury being then poured in the operation goes on, the quantity ofmercury being regulated somewhat by the richness of the ores. In a fullsized mill from one to four or five pounds is suflicient. As the mullerrevolves it constantly passes over the mercury spreading it out in athin stratum upon the bottom, while at the same time that it sweeps overit also agitates the ores, the lightest spangle of gold in which will itbrought into contact be caught by the mercury. The motion of the mulleris such as, while carrying around the whole mass of ores in the twocompartments formed by said muller, to cause a continual change of thatin one side to that in the other, in order to do which allmust passbeneath in a very thin stratum, and thus be brought into contact withthe mercury. This action is to be maintained for such a period of timeas may be found necessary, requiring generally from one to two hours toexhaust a charge.

It will thus be, seen that mine is not a rapid process, but I claim thatit is a certain for discharging the exhausted ores the plug 4 in thespout is to be removed, and the refuse allowed to flow out; this will bedone slowly, the muller still continuing in operation until the wholehas been discharged as nearly as may be. The amalgamated mercury willnow be exposed and may be exam ined. If it is still capable of taking upmore gold, the tub may be filled up with a fresh supply of ore; ifotherwise, then stop the spindle 0), lift the driving arm off the pinson L, turn the button ((5'), take out the wedge (d), when the tub may betilted over as seen in the duplicate lines Fig. II. The plug being thentaken out of the spout (70) the mercury is readily removed. The whole ofthe mercury by my process is saved, while by the old a large quantity islost with the waste ores, or in the crevices of the machines. The tubmay now be tilted back and the work continued as before.

I claim The machine herein described for effecting the completeamalgamation of precious metals from ores containing such metalsconsisting of a double concave muller with grooved bottom extendingdiametrically from side to side of the tub A, leaving spaces or chamberson each side of it and revolving in said tub upon a central and verticalaxis substantially as set forth.

In witness whereof I have hereunto subscribed my name.

J OPH ALCIDE BERTOLA.

Witnesses:

J. P. PIRSSON, S. H. MAYNARD.

